Method and system for conditioning air in an enclosed environment with distributed air circulation systems

ABSTRACT

A system for conditioning air in a building including a fan-coil unit arranged adjacent to or within an indoor space within the building and additionally configured to at least one of heat and cool the air of the indoor space, and a scrubber arranged adjacent to or within the indoor space, the scrubber configured during a scrub cycle for scrubbing of indoor air from the indoor space. The scrubber includes one or more adsorbent materials arranged therein to adsorb at least one predetermined gas from the indoor air during the scrub cycle, and an exhaust, wherein the scrubber is configured during a purge cycle to direct a purging air over and/or through the adsorbent materials to purge at least a portion of the at least one predetermined gas adsorbed by the adsorbent materials during the scrub cycle from the adsorbent materials and thereafter exhausting the flow via the exhaust.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/064,584, filed Mar. 8, 2016, titled “Method and System forConditioning Air in an Enclosed Environment with Distributed AirCirculation Systems,” which in turn is a continuation of U.S. patentapplication Ser. No. 14/359,280, filed May 19, 2014, titled the same(since issued as U.S. Pat. No. 9,316,410), which is a national stageapplication of International Patent Application No. PCT/US2012/065600,filed Nov. 16, 2012, titled the same, which in turn claims priority to:U.S. Provisional Patent Application No. 61/560,824, filed Nov. 17, 2011and entitled “Method and System for Treating Air in an EnclosedEnvironment”; U.S. Provisional Patent Application No. 61/560,827, filedNov. 17, 2011 and entitled “Method and System for ImprovedAir-Conditioning”; and U.S. Provisional Patent Application No.61/704,850, filed Sep. 24, 2012 and entitled “Method and System forTreating Air in an Enclosed Environment with Distributed Air CirculationSystems”. The disclosures of the above applications are incorporatedherein by reference in their entireties.

TECHNICAL FIELD

The present application generally relates to systems for conditioningair in an enclosed environment and more particularly to systems forconditioning air in an enclosed environment comprising distributed aircirculation systems.

BACKGROUND

Indoor air within and around enclosed environments, such as buildings,vehicles and structures, is affected by a plurality of contaminants.Among these contaminants, often with the highest concentration, iscarbon dioxide (CO₂). There are other contaminants which may appear inrelatively lower concentrations yet are no less important to monitorand/or reduce. A class of such contaminants is a group of species oforganic vapors, broadly referred to as Volatile Organic Compounds (VOC).Contaminate gases (e.g., CO₂) and VOCs, and corresponding vaporsthereof, may collectively be referred to as a “gas(es)”. The sources ofthese contaminants include, inter alia, the human occupantsthemselves—from respiration and perspiration to clothing andcosmetics—as well as building materials, equipment, food and consumerproducts, cleaning materials, office supplies or any other materialswhich emit VOCs. Other classes of contaminants are inorganic compoundsand microorganisms such as bacteria, viruses, mold, fungi and airborneparticles. Additional gaseous contaminants may be sulfur oxides, nitrousoxides, radon, or carbon monoxide.

Heating, Ventilation and Air-Conditioning (“HVAC”) is used in virtuallyevery modern building. One of the goals of HVAC systems is to provide acomfortable and healthy environment for the enclosed environmentoccupants, in terms of temperature, humidity, composition and quality ofair.

There are various HVAC system configurations known in the art.

A central HVAC system generally includes one or more central airhandling units, which is operative to adjust the temperature or humidityof air received therein. The air exiting the central air handling unitis supplied to the enclosed environment via an air circulation system.In the central HVAC system the air circulation system is formed withducts directing the supply air from the central air handling unit tovarious locations in the enclosed environment. In enclosed environments,such as buildings, comprising a plurality of indoor spaces, such asrooms, a network of ducts direct the supply air into each room. The airexiting the enclosed environment is returned to the central air handlingunit.

As noted above, in order to maintain good air quality, not all the airis returned. Some of the air is exhausted out of the enclosedenvironment and is replaced by an intake of fresh air from the outside.This is sometimes referred to as “fresh air”, “makeup air” orventilation. Such replacement of the air dilutes the contaminants withinthe indoor air and helps maintain good air quality in the enclosedenvironment.

However, there are a number of drawbacks to fresh air ventilation,including the energy required to condition the outdoor air, as well asthe potential introduction of pollutants and contaminants from theoutside into the enclosed environment. One possible solution to thesedrawbacks is to selectively remove the contaminants from indoor air, andcertain schemes have been proposed for this purpose in conjunction withcentral HVAC systems. For example, a system for removing thecontaminants from indoor air in a central HVAC system is disclosed inapplicant's U.S. Pat. No. 8,157,892, which is incorporated herein byreference in its entirety.

Selective contaminant removal from the central HVAC system is performedby directing the return air flowing within the ducts to a contaminantremover system and thereafter introducing the now treated return airback into the ducts. Generally the return air is directed to thecontaminant remover system from the ducts directing the return air fromthe enclosed environment to the central air handling unit.

An alternative HVAC system is a distributed air circulation system. Thisdistributed system generally conveys chilled (or heated) fluid to theplurality of indoor spaces, such as rooms, within the enclosedenvironment, where local air circulation units, such as fan-coil unitscirculate the indoor air. The fan-coil unit generally comprises a coilchilled (or heated) by the fluid. The coil is provided for adjusting thetemperature or humidity of the circulated air and a fan or blower isprovided for circulating the indoor air.

The chilled or heated fluid can originate from a centralized chilling orheating system shared by a plurality of fan-coil units, or from a singlededicated heat pump unit. As known in the art, the fluid can be suppliedby a Variable Refrigerant Flow (VRF) system, a Fixed Refrigerant Flowsystem, or by a direct expansion (DX) system. In other distributed aircirculation systems the fluid may be water.

The fan coil unit is placed within a room or space, typically within arecess in the ceiling or walls of the room. The fan coil unit may beplaced in a plenum adjacent to the room. The circulating air flows fromthe air circulation unit into the room substantially without reliance onducts (i.e. a ductless supply) and back from the room or space towardsthe air.

In order to maintain good air quality, some of the air is released outof the enclosed environment and is replaced by an intake of freshoutdoor air. Such replacement of the air dilutes the contaminants withinthe indoor air and helps maintain good air quality in the enclosedenvironment. The outdoor air generally enters the enclosed environmentvia a duct.

In some distributed air circulation systems, a central fresh airpre-conditioning unit initially cools (or heats) the outdoor air priorto entering ducts leading to the various rooms or fan-coil units insidethe building. In other distributed air circulation systems the outdoorair directly enters the room, plenum or the air circulation unit whereinthe outdoor air temperature is adjusted.

The energy required to condition the outdoor air, as well as thepotential introduction of pollutants and contaminants from the outdoorinto the enclosed environment are significant deficiencies of theoutside air ventilation in these systems.

Embodiments of the present disclosure are directed to remedy thesedeficiencies.

SUMMARY

There is thus provided according to some embodiments of the presentdisclosure a system for conditioning air in a building including afan-coil unit arranged adjacent to or within an indoor space within thebuilding and additionally configured to at least one of heat and coolthe air of the indoor space, and a scrubber arranged adjacent to orwithin the indoor space, the scrubber configured during a scrub cyclefor scrubbing of indoor air from the indoor space. The scrubber includesone or more adsorbent materials arranged therein to adsorb at least onepredetermined gas from the indoor air during the scrub cycle, a sourceof outdoor air, and an exhaust, wherein the scrubber is configuredduring a purge cycle to direct a purging air flow received from thesource of outdoor air over and/or through the adsorbent materials topurge at least a portion of the at least one predetermined gas adsorbedby the adsorbent materials during the scrub cycle from the adsorbentmaterials and thereafter exhausting the flow via the exhaust.

According to some embodiments of the present disclosure, the fan-coilunit may be supplied a refrigerant or heating fluid from a VariableRefrigerant Flow (VRF) system. The fan-coil unit may be supplied chilledor heated water from a central chiller or boiler. Flow of indoor airfrom the indoor space to the scrubber or from the scrubber to the indoorspace may be ductless. The predetermined gas may include carbon dioxide,volatile organic compounds, sulfur oxides, radon, nitrous oxides orcarbon monoxide. The at least one of the adsorbent materials may includegranular adsorbent particles, solid supported amines, activated carbon,clay, carbon fibers, carbon cloth, silica, alumina, zeolite, syntheticzeolite, hydrophobic zeolite, natural zeolite, molecular sieves,titanium oxide, polymers, porous polymers, polymer fibers or metalorganic frameworks. At least one of the adsorbent materials may becontained in one or more removable cartridges. At least one gasdetection sensor for detecting a level of the at least one predeterminedgas may be provided.

According to some embodiments of the present disclosure, the scrubbermay further include at least one of a damper and a fan configured toswitch the scrubber from the scrub cycle to the purge cycle. The systemmay further include a controller to perform the switching, wherein thecontroller is programmed to switch between the scrub cycle and the purgecycle by at least one of a preset schedule, a predetermined level of thepredetermined gas, the indoor space occupancy level, a manual trigger, asignaled command or an externally signaled command. The system mayfurther include an air plenum over a ceiling of the indoor space oradjacent to the indoor space, wherein the air plenum houses the fan-coilunit. The system may further include an air plenum over a ceiling of theindoor space or adjacent to the indoor space, wherein the air plenumhouses the scrubber.

According to some embodiments of the present disclosure, the fan-coilunit may include housing, and wherein at least a portion of the scrubbermay be housed within the housing. A fan of the fan-coil unit may beconfigured to direct indoor air flow into the scrubber. The system mayfurther include a heater, wherein the received outdoor air is heated bythe heater. The heater may be a heat pump, an electric heating coil, acoil or radiator with heated fluid supplied from a central heatingsystem, a solar heater or a furnace. The heat pump may remove heat fromthe indoor air. The heated outdoor air may be heated prior to beingsupplied to the scrubber.

According to some embodiments of the present disclosure, the system mayinclude at least one additional air treatment component such as an airionizer, an ozone source, a source of radiation, a membrane, foam,paper, fiberglass, a heater, a particle filter, an ultravioletanti-microbial device, an ion or plasma generator, an oxide, a catalystor a chemical catalyst. The additional air treatment component may beplaced within the scrubber. The additional air treatment component maybe placed within the indoor space. The indoor air flows out of thefan-coil unit via a duct and the additional air treatment component maybe placed within the duct.

According to some embodiments of the present disclosure, a plurality ofindoor spaces may be provided and a plurality of fan-coil units may beprovided. The plurality of fan-coil units may be arranged adjacent to orwithin the plurality of indoor spaces and the scrubber may be configuredduring a scrub cycle for scrubbing of indoor air from the plurality ofindoor spaces.

There is thus provided according to some embodiments of the presentdisclosure an air treatment system for conditioning air in a building,including a scrubber configured during a scrub cycle for scrubbing ofair from an indoor space of the building and positioned within oradjacent the indoor space, the scrubber including one or more adsorbentmaterials arranged therein to adsorb at least one predetermined gas fromthe air of the indoor space during the scrub cycle, a source of outdoorair, and an exhaust, wherein the scrubber is configured during a purgecycle to direct a purging air flow, received via the source of outdoorair, over and/or through the adsorbent materials to purge at least aportion of the at least one predetermined gas adsorbed by the adsorbentmaterials during the scrub cycle from the adsorbent materials andthereafter exhausting the flow, via the exhaust.

According to some embodiments of the present disclosure, the scrubbermay be configured to supply scrubbed air exiting the scrubber to theindoor space. The scrubber may be configured to supply scrubbed air to afan-coil unit arranged adjacent to or within the indoor space.

There is thus provided according to some embodiments of the presentdisclosure a method for conditioning air in a building, includingcirculating indoor air of an indoor space via a fan-coil unit,optionally heating or cooling the circulated indoor air, scrubbing theindoor air during a scrub cycle using a scrubber placed within oradjacent to the indoor space, the scrubber including one or moreadsorbent materials arranged therein to adsorb at least onepredetermined gas from the air of the indoor space during the scrubcycle, a source of outdoor air, and an outdoor exhaust, flowing apurging air flow received via the source of outdoor air over and/orthrough the one or more adsorbent materials so as to purge the adsorbentmaterials of at least a portion of the at least one gas adsorbed by theone or more adsorbent materials, and thereafter exhausting the purgingair flow via the exhaust.

There is thus provided according to some embodiments of the presentdisclosure a system for conditioning air in a building including aplurality of indoor spaces within the building, a plurality of fan-coilunits arranged adjacent to or within the plurality of indoor spaces andadditionally configured to at least one of heat and cool the air of theplurality of indoor spaces, and a scrubber arranged adjacent to orwithin the building, the scrubber configured during a scrub cycle forscrubbing of indoor air from the plurality of indoor spaces, thescrubber including one or more adsorbent materials arranged therein toadsorb at least one predetermined gas from the indoor air during thescrub cycle, a source of outdoor air, and an exhaust, wherein thescrubber is configured during a purge cycle to direct a purging air flowreceived from the source of outdoor air over and/or through theadsorbent materials to purge at least a portion of the at least onepredetermined gas adsorbed by the adsorbent materials during the scrubcycle from the adsorbent materials and thereafter exhausting the flowvia the exhaust.

According to some embodiments of the present disclosure, the fan-coilunit may be supplied refrigerant or heating fluid from a variablerefrigerant flow (VRF) system. More than one of the plurality offan-coil units may be supplied refrigerant or heating fluid from acommon variable refrigerant flow (VRF) system. The fan-coil unit may besupplied chilled or heated water from a central chiller or boiler.Scrubbed air exiting the scrubber may be directed to the plurality ofindoor spaces via conduits. Indoor air may be directed to the scrubberfrom the plurality of indoor spaces via conduits. The conduits may beinstalled and configured for directing the indoor air from the pluralityof indoor spaces to the scrubber. The conduits may be pre-existing inthe building and may be configured for ventilation, elevators exhaust orsmoke exhaust in the building. A pre-conditioning unit may be configuredto at least heat or cool outside air or scrubbed air exiting thescrubber and direct the pre-conditioned air to the plurality of indoorspaces. The pre-conditioned air may be directed to the plurality ofindoor spaces via conduits.

BRIEF DESCRIPTION OF THE DRAWINGS

The principles and operations of the systems, apparatuses and methodsaccording to some embodiments of the present disclosure may be betterunderstood with reference to the drawings, and the followingdescription. These drawings are given for illustrative purposes only andare not meant to be limiting.

FIG. 1 is a simplified schematic illustration of a system forconditioning air in an enclosed environment according to someembodiments of the present disclosure;

FIG. 2 is a simplified schematic illustration of another system forconditioning air in an enclosed environment according to someembodiments of the present disclosure;

FIG. 3 is a simplified schematic illustration of yet another system forconditioning air in an enclosed environment according to someembodiments of the present disclosure;

FIG. 4 is a simplified schematic illustration of still another systemfor conditioning air in an enclosed environment according to someembodiments of the present disclosure;

FIG. 5 is a simplified schematic illustration of another system forconditioning air in an enclosed environment according to someembodiments of the present disclosure;

FIG. 6 is a simplified schematic illustration of yet another system forconditioning air in an enclosed environment according to someembodiments of the present disclosure;

FIG. 7 is a simplified schematic illustration of still another systemfor conditioning air in an enclosed environment according to someembodiments of the present disclosure;

FIG. 8 is a simplified schematic illustration of yet another system forconditioning air in an enclosed environment according to someembodiments of the present disclosure;

FIGS. 9A-9E are each a simplified schematic illustration of stillanother system for conditioning air in an enclosed environment accordingto some embodiments of the present disclosure;

FIGS. 10A and 10B are each a simplified schematic illustration ofanother system for conditioning air in an enclosed environment accordingto some embodiments of the present disclosure; and

FIGS. 11A-11D are each a simplified schematic illustration of anothersystem for conditioning air in an enclosed environment according to someembodiments of the present disclosure.

DETAILED DESCRIPTION

FIG. 1 is a simplified schematic illustration of a system 100 forconditioning air in an enclosed environment 102 (e.g., the interior of abuilding) according to some embodiments of the present disclosure. FIG.2 is another simplified schematic illustration of a system 104 forconditioning air in the enclosed environment 102 according to someembodiments of the present disclosure, and FIG. 3 is yet anothersimplified schematic illustration of a system 106 for conditioning airin the enclosed environment 102 according to some embodiments of thepresent disclosure. As seen in FIGS. 1-3, the respective systems 100,104 and 106 for conditioning air in the enclosed environment 102 eachcomprise a distributed air circulation system 110.

The enclosed environment 102 may comprise an office building, acommercial building, a bank, a residential building, a house, a school,a factory, a hospital, a store, a mall, an indoor entertainment venue, astorage facility, a laboratory, a vehicle, an aircraft, a ship, a bus, atheatre, a partially and/or fully enclosed arena, an education facility,a library and/or other partially and/or fully enclosed structure and/orfacility which can be at times occupied by equipment, materials, liveoccupants (e.g., humans, animals, synthetic organisms, etc.) and/or anycombination thereof.

According to some embodiments, the enclosed environment 102 may comprisea plurality of indoor spaces 120, such as rooms, cubicles, zones in abuilding, compartments, railroad cars, caravans or trailers, forexample. Adjacent to the indoor space 120 may be an air plenum 124,typically located above the ceiling of the indoor space 120. As seen inFIG. 1, each indoor space 120 is associated with a separate air plenum124, though a common air plenum 124 may be associated with a pluralityof indoor spaces 120.

According to another embodiment, the enclosed environment 102 maycomprise a single indoor space 120. An exemplary enclosed environment102 comprising a single indoor space 120 will be further described inreference to FIG. 7.

The distributed air circulation system 110 conveys chilled or heatedfluid to local air circulation units 126. Typically, nearly each indoorspace 120 is associated with a local air circulation unit 126, whichcirculates and cools or heats the indoor air of the indoor space 120. Asseen in FIGS. 1 and 3, each indoor space 120 is associated with an aircirculation unit 126. In FIG. 2 only the left side indoor space 120 isassociated with an air circulation unit 126.

In the embodiments shown in FIGS. 1-11C the air circulation unit 126comprises a fan-coil unit 128. It is appreciated that the aircirculation unit 126 may comprise any other suitable device forcirculating and cooling or heating air in indoor spaces 120, such as ablower-coil unit, for example. In some embodiments the air circulationunit 126 may be a component in a split unit system.

The chilled or heated fluid may originate from a centralized chilling orheating system shared by a plurality of air circulation units, or from asingle dedicated heat pump or boiler (not shown). In accordance withsome embodiments, the fluid may be supplied by a Variable RefrigerantFlow (VRF) system. In accordance with another embodiment the fluid maybe supplied by a Fixed Refrigerant Flow system or by a direct expansion(DX) system. In other distributed air circulation systems the fluid maybe water.

The fan-coil unit 128 may comprise a housing 130 including a fan 134 andcoils 136. The coils 136 are typically cooled or heated by the fluid.The coils 136 may comprise a cooling coil 138 and/or a heating coil 140and/or any other suitable cooling or heating means, such as radiators,electrical heaters, chillers, heat exchangers, nozzles or jets, forexample.

At least a portion of the indoor air may exit the indoor space 120 asreturn air 150. In accordance with some embodiments, the return air mayenter the air plenum 124. Typically the return air 150 enters the airplenum 124 without flowing through a duct, though in some embodiments aduct (not shown) may be provided.

In accordance with other embodiments the indoor space 120 may beassociated with an adjacent area above its ceiling instead of the airplenum 124. The return air 150 may flow within a duct (not shown)located in the area above the ceiling to the fan-coil unit 128.

The fan 134 draws the return air 150 to enter fan-coil unit 128, via anentry port 154, and flow in the vicinity of coils 136 for heating orcooling thereof. In FIGS. 1-3 the coils 136 are placed downstream thefan 134. Alternatively, the coils 136 may be placed intermediate the fan134 and the entry port 154 or at any other suitable location. Return air150 may flow through a particle filter 158 for removing dust andairborne particles therefrom.

Conditioned air 160, i.e. return air cooled or heated by the coils 136,exits via an exit port 164. The conditioned air 160 enters the indoorspace 120 for circulation thereof. The conditioned air 160 may flow fromthe fan-coil unit 128 into the indoor space via a duct 168 or mayductlessly flow into the indoor space 120.

A portion of the indoor air may be exhausted from the enclosedenvironment 102 as exhaust air 170 into the ambient or any locationoutside the enclosed environment 102. Any suitable means, such as ablower or a fan (not shown) may be used to exhaust the exhaust air 170.The exhaust air 170 may exit the indoor space 120, via an exhaust port172, and/or may exit the air plenum 124, via an exhaust port 176 or viaan exhaust port (not shown) of the fan-coil unit 128.

In standard distributed air circulation systems fresh, outdoor air ornamely “makeup air” 180 may be introduced into the enclosed environment102 for supplying nominally fresh, good quality air combining with thereturn air 150. The outdoor air 180 may be introduced into the enclosedenvironment in any suitable manner, such as by a network of ducts 184.In the embodiment shown in FIGS. 1 and 3 the outdoor air 180 may beintroduced directly into each of the indoor spaces 120, via an entryport 188, or the outdoor air 180 may be introduced into the air plenum124, via an entry port 190. In another embodiment, the outdoor air 180may be introduced directly into each fan-coil unit 128, as shown in FIG.2. As seen in FIG. 2, the duct 184 is directed to introduce the outdoorair 180 into the fan-coil unit 128 prior to the particle filter 158,though the outdoor air 180 may be introduced into the fan-coil unit 128at any suitable location therein.

A scrubber 200 is provided to reduce the concentration of contaminantspresent in the return air 150 flowing therein. A contaminant may be apredetermined gas or vapor, such as CO₂, for example. The scrubber 200may comprise a CO₂ scrubber 204. Examples of CO₂ scrubbers are disclosedin applicant's U.S. Pat. No. 8,157,892, which is incorporated herein byreference in its entirety. The CO₂ scrubber 204 may comprise anysuitable material for capturing CO₂, such as a CO₂ adsorbent material.An exemplary CO₂ adsorbent material may be a solid support materialsupporting an amine-based compound, such as disclosed in applicant's PCTapplication PCT/US12/38343, which is incorporated herein by reference inits entirety. Other adsorbent materials include, but are not limited to,granular adsorbent particles, clay-based adsorbents, activated carbon,zeolites, natural zeolite, activated charcoal, molecular sieves, silica,silica gel, porous silica, alumina, porous alumina, titanium oxide,carbon fibers, porous polymers, polymer fibers and metal organicframeworks.

The CO₂ scrubber 204 may include a plurality of CO₂ scrubbing cartridges210. The CO₂ scrubbing cartridges 210 may comprise the adsorbentmaterial formed as a solid or flexible sheet or as granules supported byporous surfaces. The scrubbing cartridges 210 may be arranged in anysuitable arrangement. For example, the CO₂ scrubbing cartridges 210 maybe parallelly arranged therebetween. Alternatively, as seen in FIG. 1,the CO₂ scrubbing cartridges 210 may be staggeringly arrangedtherebetween. This staggered arrangement allows substantially parallelair flow paths of the return air 150 therethrough. Exemplary CO₂scrubbing cartridges and modules are disclosed in applicant's US PatentPublication No. 20110198055, which is incorporated herein by referencein its entirety.

An additional contaminant may be VOCs. The scrubber 200 may comprise aVOC scrubber 214 for removing VOCs from the return air 150 flowingtherethrough. The VOC scrubber 214 may comprise any suitable adsorbentmaterial for adsorbing the VOCs. For example VOC adsorbent materials maycomprise a hydrophobic zeolite, natural zeolite, synthetic zeolite,carbon cloth, activated carbon, a molecular sieve, polymers, a thinpermeable sheet structure, carbon fibers, or granular adsorbentparticles attached to a sheet of some other permeable material, such aspaper, cloth or fine mesh, for example.

The VOC scrubber 214 may be arranged in any suitable arrangement, suchas a bed of granular material, a flat sheet, or a pleated sheet, asshown in FIG. 1.

A filter 216 may be provided for removing additional contaminants, suchas dirt, small airborne particles and may comprise any suitable filteror adsorbent material.

Operation of the scrubber 200 may comprise a scrub cycle and a purgecycle. During the scrub cycle, the contaminants are captured andadsorbed by the adsorbent material or any other means. A portion of thereturn air 150 may be urged by a scrubber fan 224 to flow into thescrubber 200. The return air 150 may flow into the scrubber 200 via anentry port 226 including an entry damper 228, when positioned in an openstate.

The volume of the portion of the return air 150 flowing into thescrubber 200 may be controlled by the scrubber fan 224 and/or damper228, or by any other suitable means. In some embodiments, a volume ofapproximately 1%-50% of the fan-coil airflow (namely air flowing throughthe fan-coil unit 128) may enter the scrubber 200. In some embodiments,a volume of approximately 1%-25% of the fan-coil airflow may enter thescrubber 200. In some embodiments, a volume of approximately 1%-10% ofthe fan-coil airflow may enter the scrubber 200. The remaining returnair 150, which bypassed the scrubber 200, may flow directly through thefan-coil unit 128 or to the indoor space 120.

The scrubber fan 224 may be placed in any suitable location within thescrubber 200, such as upstream in a “push” mode, i.e. intermediate theentry port 226 and the CO₂ scrubber 204. Alternatively, as seen in FIG.1, the scrubber fan 224 may be placed downstream in a “pull” mode i.e.after the CO₂ scrubber 204.

The return air 150 may flow through the filter 216, CO₂ scrubber 204and/or the VOC scrubber 214. The now scrubbed air flows out of thescrubber 200 via an exit port 230 including an exit damper 232, whenpositioned in an open state. The scrubbed air flows into the fan-coilunit 128 and may be conditioned by being cooled or heated therein. Theconditioned air 160 may flow from the fan-coil unit 128 into the indoorspace 120.

Scrubbing the return air within the scrubber 200, according to someembodiments, allows reducing or eliminating the volume of fresh, outdoorair 180, which is required to provide for maintaining good air qualitytherein. Accordingly, the energy required to condition the outdoor air180 is reduced or eliminated. Additionally, introduction of potentialpollutants and contaminants from the outdoor air 180 into the enclosedenvironment 102 is reduced or eliminated. In some embodiments the volumeof fresh, outdoor air 180 may be reduced approximately to a minimallyrequired volume of the exhausted air 170, so as to maintain pressureequilibrium within the enclosed environment 102. Moreover, superiorindoor air quality is provided.

The volume of fresh, outdoor air 180 may be reduced in any suitablemanner such as by reducing the volume of outdoor air 180 prior to flowin ducts 184 or by partially or fully closing dampers (not shown) withinthe enclosed environment 102 for controlling the volume of outdoor air180 introduced therein.

Following the capture and scrubbing of the contaminants in the scrubcycle, the adsorbent material may be regenerated during the purge cycleby urging the release of the contaminants from the adsorbent material.

The regeneration may be performed in any suitable manner. For example,in some embodiments, regeneration may be performed by streaming a purgegas 240 over and/or through the adsorbent material for release of atleast a portion of the contaminants therefrom.

For example, during the purge cycle the purge gas 240 flows into thescrubber 200 via an entry conduit 244 including an entry damper 246,when positioned in an open state, while the entry damper 228 and exitdamper 232 may be closed. A fan 247 may be provided for urging flow ofthe purge gas 240 within the scrubber 200. The fan 247 may be placed inany suitable location, such as in an exhaust conduit 248. Alternatively,the fan 247 may be omitted.

Thus, in some embodiments, it is seen that switching the scrubberoperation from the scrub cycle to the purge cycle may be performed bythe dampers and/or fans or any other suitable means.

In accordance with some embodiments the purge gas 240 comprises outdoorair.

The outdoor air may be provided to the scrubber 200 from any source ofoutdoor air. For example, the source of outdoor air may be ambient airflowing directly from the ambient, i.e. out of the enclosed environment102, into the scrubber 200, as shown in FIG. 1. Alternatively, theoutdoor air may flow from the ambient into the scrubber 200 via ducts(not shown). Additionally, the source of outdoor air may be from otherlocations near the space 120, such as from a pier or elevator shaft.

As shown in FIGS. 1-3, in some embodiments, the purge gas 240 may flowduring the purge cycle in the opposite direction of the return air flowduring the scrub cycle, such as from entry conduit 244 to the exhaustconduit 248. Alternatively, the purge gas 240 may flow during the purgecycle in the same direction of the return air flow, such as from exhaustconduit 248 to entry conduit 244.

The exhaust conduit 248 may include an exit damper 250.

It is noted that the entry conduit 244 may be replaced by an apertureallowing the purge gas 240 to flow into the scrubber 200. The exhaustconduit 248 may be replaced by any exhaust allowing the purge gas 240 toflow out of the scrubber 200.

As seen in FIGS. 1-11C, in some embodiments, the purge gas 240 exitingthe exhaust conduit 248 is discharged into the ambient, out of theenclosed environment 102. Alternatively, the purge gas 240 may flow outof the exhaust conduit 248 to existing exhaust ducts in the enclosedenvironment such as an air exhaust typically furnished in a bathroom ofthe enclosed environment 102 or openings such as windows. Additionally,purge gas 240 exiting the exhaust conduit 248 may flow to a volume inthe enclosed environment 102, such as a stairwell, sewerage system orsmoke control systems. Moreover, purge gas 240 may be directed to flowinto a pressure vessel (not shown) for eventual release of the purge gas240 therefrom.

The purge gas 240 may be heated prior to regeneration of the scrubber200 by any suitable method, as will be further described in reference toFIGS. 10A and 10B.

In accordance with some embodiments, the purge gas 240 may be heatedwithin a range of approximately 20-120° C. In accordance with someembodiments, the purge gas 240 may be heated to a temperature of lessthan 80° C. In accordance with some embodiments, the purge gas 240 maybe heated to a temperature of less than 50° C. In accordance with someembodiments, the purge gas 240 may enter the scrubber 200 at the ambienttemperature.

Regeneration of the adsorbent material removes the contaminants from theadsorbent material. Therefore, the scrubber 200 can be repeatedly usedfor removing contaminants from the indoor space 120 without requiringreplacement of the adsorbent material. Accordingly, the scrubber 200described herein has a significantly long operating life.

In the distributed air circulation system 110, according to someembodiments, the flow of the return air 150 into and out of the scrubber200 and into and out of the fan-coil unit 128 may be at least partiallyductless. For example, as shown in FIGS. 1-3, the flow of the return air150 into the scrubber 200 is ductless and a portion of the return air150 is urged by the scrubber fan 224 to flow from the air plenum 124into the scrubber 200. The flow of the return air 150 from the airplenum 124 into the fan-coil unit 128 is shown to be ductless and isurged by the fan 134 to flow therein. The flow of the conditioned airout of the fan-coil unit 128 may be ductless or, as shown in FIGS. 1-3,the duct 168 is provided.

In some embodiments, such as seen in FIGS. 1 and 2, the scrubbed airexiting the scrubber 200 may flow into the air plenum 124 and enter intothe fan-coil unit 128 without a duct.

In other embodiments, as seen in FIG. 3, the scrubbed air exiting thescrubber 200 may flow into the fan-coil unit 128 via a duct 250.

In FIG. 4, a system 254 for conditioning air in the enclosed environment102 is substantially similar to the respective systems 100, 104 and 106of FIGS. 1-3. As seen in FIG. 4, exhaust ports 172 or 176 are notincluded and similarly outdoor air 180 is not introduced into the indoorspaces 120 or the air plenum 124. A portion of the return air 150 isscrubbed in the scrubber 200, thereby providing good air quality to theindoor space 120. Therefore, introduction of the fresh, outdoor air 180for maintaining good air quality is unnecessary and the energy requiredto condition the outdoor air 180 is also eliminated. Additionally,introduction of potential pollutants and contaminants from the outdoorair 180 into the enclosed environment 102 is eliminated.

A portion of the return air 150 may initially flow to the scrubber 200and thereafter the scrubbed air may flow into the fan-coil unit 128, asshown in FIGS. 1-4. Alternatively, the return air 150 may initially flowthrough the fan-coil unit 128, as shown in FIG. 5.

In FIG. 5, a system 258 for conditioning air in the enclosed environment102 is shown. As seen in FIG. 5, the return air 150 initially flows intothe fan-coil unit 128. A portion 260 of the conditioned air exiting thefan-coil unit 128 may be directed into the indoor space 120 and aportion 262 of the conditioned air may flow into the scrubber 200. Thescrubbed air exiting the scrubber 200 may be directed into the indoorspace 120.

In some embodiments the fan-coil unit 128 may be placed in the airplenum 124, as seen in FIGS. 1-5. In other embodiments the fan-coil unit128 may be placed within the indoor space 120 on a floor 270 (FIG. 6) orin proximity thereto, near a wall 274 or on a ceiling 276 or inproximity thereto. The scrubber 200 may be placed in the air plenum 124,as seen in FIGS. 1-5. In other embodiments the fan-coil unit 128 may beplaced within the indoor space 120 under the floor 270 or in proximitythereto, near the wall 274 or in proximity thereto or on the ceiling 276or in proximity thereto.

In FIG. 6 a system 278 for conditioning air in the enclosed environment102 is shown. In the left side indoor space 120 the fan-coil unit 128 isshown to be mounted horizontally beneath the ceiling 276 and in theright side indoor space 120 the fan-coil unit 128 is shown to be mountedvertically on the wall 274. The indoor air, illustrated by arrows 280,circulates within the indoor space 120. A portion of the indoor air 280may enter the scrubber 200. The scrubber 200 may be placed in anysuitable location within the indoor space 120, such as in proximity tothe ceiling 276, for example.

The scrubbed air exits the scrubber 200 into the indoor space 120 forfurther circulation thereof.

In FIG. 7, a system 288 for conditioning air in the enclosed environment102 is shown. As seen in FIG. 7, the enclosed environment 102 maycomprise a single indoor space 120. A plurality of fan-coil units 128may be provided for conditioning the return air 150 and circulating theconditioned air back into the indoor space 120. The plurality offan-coil units 128 may be placed in the air plenum 124, as shown in FIG.7, or in any suitable location within the indoor space 120, as describedin reference to FIG. 6.

A single scrubber 200 may be provided to scrub the indoor air, as shownin FIG. 7, or a plurality of scrubbers 200 may be provided. In someembodiments each scrubber 200 may be associated with a specific fan-coilunit 128. In some embodiments the plurality of scrubbers 200 may beplaced within the indoor space 120 and may not be associated with aspecific fan-coil unit 128.

The scrubber 200 may be placed in any suitable location within theenclosed environment 102 as described in reference to FIG. 6. In FIG. 7the scrubber is placed within the indoor space 120.

In some embodiments, as shown in FIG. 7, a portion of the indoor air 280may be exhausted out of the enclosed environment via exhaust ports 286.Fresh, outdoor air 180 may be introduced into the indoor space 120 orany other suitable location, via a duct 290. In some embodiments thefresh, outdoor air 180 may be cooled or heated prior to entrance intothe enclosed environment by a fresh air, pre-conditioning unit 292,thereby reducing a degree of cooling or heating required by the fan-coilunits 128.

Scrubbing the indoor air 280 within the scrubber 200 allows for reducingthe volume of fresh, outdoor air 180 required for maintaining good airquality within the indoor space 120. Accordingly, the energy required tocondition the outdoor air 180 is reduced. Additionally, introduction ofpotential pollutants and contaminants from the outdoor air 180 into theenclosed environment 102 is reduced.

In some embodiments, fresh, outdoor air 180 may not be introduced intothe enclosed environment 102 of FIG. 7.

In FIG. 8, a system 300 for conditioning air in the enclosed environment102 is shown. As seen in FIG. 8, the enclosed environment 102 comprisesa plurality of indoor spaces 120 each associated with its fan-coil unit128. In a non-limiting example shown in FIG. 8, the fan-coil units 128are set above the ceiling, within or without the air plenum 124. Thefan-coil units 128 may have a common supply of a refrigerant fluidsupplied from a shared chiller or heat pump (not shown). In accordancewith some embodiments, the refrigerant fluid may comprise chilled wateror may be supplied by a variable refrigerant flow (VRF) system. Aportion of return air 304 may flow out of each indoor space 120 directlyto the fan-coil unit or into the air plenum 124. This portion of thereturn air 304 may flow into the fan-coil unit 128 for conditioningthereof and circulation into the indoor space 120. Some of the returnair 304 may be exhausted out of the enclosed environment 102, such asvia exhaust ports 310 located in each of the air plenums 124 or anyother suitable location.

Another portion of return air 314 may be directed to flow into a sharedscrubber 200, via conduits 320 or without conduits by any other suitablemanner. In some embodiments the conduits 320 may be installedspecifically for flow into the scrubber 200. In other embodimentsexisting conduits or ducts in the enclosed environment (e.g. building)may be used, such as standard ducts provided for ventilation orelevators or for exhaust such as smoke exhaust.

Scrubbed air, exiting the scrubber 200, may be introduced back into theindoor spaces 120 via conduits 324 or in any other suitable manner. Insome embodiments conduits 324 may comprise existing indoor air conduitsor ducts, such as ducts 184 of FIG. 1. The scrubbed air may initiallyflow from the scrubber 200 into a fresh air pre-conditioning unit 330,such as the fresh air pre-conditioning unit 292 shown in FIG. 7. Thescrubbed air may be cooled or heated within the fresh airpre-conditioning unit 330 prior to flow in conduits 324, therebyreducing a degree of cooling or heating required by the fan-coil units128. The scrubbed air may flow from the scrubber 200 into the fresh airpre-conditioning unit 330 via a conduit 334 or by any other suitablemeans.

In some embodiments a plurality of scrubbers 200 may be provided.

The scrubber 200 may be placed in a suitable location, such as on a roof338 of the enclosed environment 102 or out of the enclosed environment102 or within the enclosed environment 102 such as in a mechanical roomor any other location.

Scrubbing the return air 314 within the scrubber 200 allows for reducingthe volume of fresh, outdoor air 340 required for maintaining good airquality within the indoor space 120. In some embodiments, such aswherein exhaust ports 310 are not provided, introduction of fresh,outdoor air 340 may be eliminated.

In FIG. 9A-9E a system 400 for conditioning air in the enclosedenvironment 102 is shown. As seen in FIG. 9A an integrated fan-coil unit410 comprises a housing or mechanical frame 412 that is connecting orotherwise shared by the scrubber 200 and the fan-coil unit 128. Returnair 150 may enter the integrated unit 410 via an entry port 416 and maybe initially filtered by filter 158. Thereafter, a portion of the returnair 150 may be scrubbed within the scrubber 200 and a remaining portionof return air may bypass the scrubber 200. The scrubbed air and thebypassed air are urged by the fan 134 to flow to the coils 136 to becooled or heated thereby. The conditioned air may exit the integratedunit 410 via an exit port 414 and duct 416 so as to be circulated intothe indoor space 120.

In the embodiment shown in FIG. 9A, the scrubber 200 is placed prior tothe fan 134 and coils 136, in respect to the direction of the return airflow. In the embodiment shown in FIG. 9B, an integrated unit 420 isprovided and the scrubber 200 is placed intermediate the fan 134 andcoils 136. In the embodiment shown in FIG. 9C an integrated unit 430 isprovided and the scrubber 200 is placed after the fan 134 and coils 136,in respect to the direction of the return air flow.

In the embodiment shown in FIG. 9D, an integrated unit 440 is provided.The entry port 226 to the scrubber 200 is provided following the fan 134and the coils 136. The exit port 230 is placed intermediate the fan 134and coils 136. Return air 150 flowing into the integrated unit 440 mayflow through filter 158. The fan 134 urges the return air 150 to flow tothe coils 136 for cooling or heating thereby. A portion of the cooled orheated air may bypass the scrubber 200 and flow out of the integratedunit 440. A remaining portion of the cooled or heated air may be urgedby scrubber fan 224 to enter the entry port 226 into the scrubber 200.The scrubbed air may exit the scrubber via exit port 230 and may becooled or heated again by the coils 136 prior to flowing out of theintegrated unit 440.

In the embodiment shown in FIG. 9E, an integrated unit 450 is provided.Here the entry port 226 to the scrubber 200 is positioned following thecoils 136. The fan 134 is positioned intermediate the coils 136 and theentry port 226. The exit port 230 is placed prior the coils 136. Returnair 150 flowing into the integrated unit 450 may flow through filter158. The fan 134 urges the return air 150 to flow to the coils 136 forcooling or heating thereby. A portion of the cooled or heated air maybypass the scrubber 200 and flow out of the integrated unit 450. Aremaining portion of the cooled or heated air may be urged by fan 134 toenter the entry port 226 into the scrubber 200. The fan 134 of thefan-coil unit 128 may be sufficient for urging the cooled or heated airto flow into the scrubber 200 and the scrubber fan may be eliminated.The scrubbed air may exit the scrubber via exit port 230 and may becooled or heated again by the coils 136 prior to flowing out of theintegrated unit 450.

The integrated units 410, 420, 430, 440 and 450 may be placed within theair plenum 124, as shown in FIGS. 9A-9E, or within the indoor space 120or any other suitable location.

Use of an integrated unit, such as shown in FIGS. 9A-9E, simplifies theinstallation or connection of the scrubber 200 and fan-coil unit 128.Additionally, in some embodiments, components of the fan-coil unit 128may be used for the scrubber 200. For example the fan 134 may be used toaid in directing air into the scrubber 200, and may even eliminate theneed for a separate scrubber fan, as seen in FIG. 9E. Moreover, thepurge gas 240 may be heated by heating coil 140 or other heating meanswithin the fan-coil unit 128.

As described in reference to FIGS. 1-9E, the purge gas 240 may be heatedprior to flow into the scrubber 200. Additionally, the purge gas 240 maybe heated within the scrubber 200, such as in entry conduit 244. Thepurge gas 240 may be heated in any suitable manner. For example, thepurge gas 240 may be heated by an electric heating coil, a coil orradiator with heated fluid supplied from a central heating system in theenclosed environment 102, solar heat, such as solar heat provided to theenclosed environment 102, an appropriately sized furnace burning gas orother fuel (not shown) for heating the purge gas 240. Some additionalexemplary methods are described in reference to FIGS. 10A and 10B.

In FIG. 10A, a system 500 for conditioning air in the enclosedenvironment 102 is shown. In accordance with some embodiments, a warmfluid may be used to heat the purge gas 240. For example, a fluid coil510, such as a copper or other metal tube, is placed at the entryconduit 244 and the coil 510 is supplied with warm fluid. In someembodiments, the warm fluid may be heated within a heating plant orboiler (not shown) provided specifically for heating the purge gas 240.In some embodiments, the warm fluid may be heated by an existing supplyof warm fluid provided in a standard enclosed environment 102, such as abuilding's hot water supply or the warm fluid provided to the heatingcoils 140 of the fan-coil unit 128.

In FIG. 10B, a system 600 for conditioning air in the enclosedenvironment 102 is shown where, according to some embodiments, a heatpump 610 may be utilized to heat the purge gas 240. Typically, the heatpump 610 comprises a condenser side, or a hot side 620. The purge gas240 may directly contact the hot side 620 and may be heated thereby.Alternatively, a heating element 624 may be heated by the hot side 620and the purge gas 240 may be heated by the heating element 624.Additionally, the hot side 620 may be used to directly heat theadsorbent material in the scrubber 200. Use of a heat pump 610 may beadvantageous, since to operate the heat pump 610 less power is requiredthan other heating means, such as electric heating, for example.

In some embodiments, an evaporator side or a cold side 630 of the heatpump 610 may be used to remove heat from the return air 150 flowingwithin the air plenum 124, or the air flowing through the fan coil unit,or any other air within the indoor space 120. The now cooled airdirectly or indirectly lessens the cooling power required by thefan-coil unit 128.

In FIGS. 11A-11D, respective systems 700, 710, 720 and 730 forconditioning air in the enclosed environment 102 according to someembodiments are shown. As seen in FIGS. 11A-11C, the systems 700, 710,720 are similar to the system 100 of FIG. 1.

In accordance with some embodiments, an air ionizer 750 or air purifiermay be provided at any suitable location within the enclosed environment102 to enhance the air quality therewithin. The air ionizer 750typically emits electrically charged ions that clean impurities from theair within the enclosed environment 102. The air ionizer 750 may beprovided to otherwise improve air quality within the enclosedenvironment 102.

The air ionizer 750 may be placed at any suitable location. For example,as seen in FIG. 11A, the air ionizer 750 is placed in the center of theindoor space 120. Additionally, the air ionizer 750 may be mounted tothe wall 274 or ceiling 276 of the indoor space 120 or any othersuitable location within the enclosed environment 102.

As seen in FIG. 11B, the air ionizer 750 may be associated with thefan-coil unit 128, and may be placed in the duct 168, for example.Turning to FIG. 11C, it is seen that the air ionizer 750 may be placedwithin the scrubber 200 at any suitable location, such as intermediatethe filter 158 and the CO₂ scrubber 204, for example.

In accordance with some embodiments, a microorganism removal device 760may be provided for removal of microorganisms including, inter alia,bacteria, viruses, molds and fungi, from the enclosed environment 102 inany suitable manner. In a non-limiting example the removal device 760may comprise an ultraviolet anti-microbial device. The removal device760 may include an air filter with a media formed of foam, paper,fiberglass, oxides, catalysts, or any other suitable material.Additionally the removal device 760 may remove the microorganisms usingan ozone source, a source of radiation, ion or plasma generators,chemical catalysts, a membrane and/or a heater.

The removal device 760 may be placed at any suitable location. Forexample, as seen in FIG. 11A, the removal device 760 is placed in thecenter of the indoor space 120. Additionally, the removal device 760 maybe mounted to the wall 274 or ceiling 276 of the indoor space 120 or anyother suitable location within the enclosed environment 102.

As seen in FIG. 11B, the removal device 760 may be associated with thefan-coil unit 128, and may be placed in duct 168, for example. Turningto FIG. 11C, it is seen that the removal device 760 may be placed withinthe scrubber 200 at any suitable location, such as intermediate thefilter 158 and the CO₂ scrubber 204, for example.

It is noted that additional contaminant removal devices may be providedwithin the systems of FIGS. 1-11D. For example, a device for removingdust in any suitable manner may be provided or a plasma generator, orchemical catalysts may be provided.

It is noted that the air ionizer 750 and the microorganism removaldevice 760 may be placed in any one of the systems shown in FIGS. 1-10B.

In FIG. 11D, the system 730 for conditioning air in an enclosedenvironment 802 is shown. The enclosed environment 802 may be similar toenclosed environment 102 of FIGS. 1-11C. As seen in FIG. 11D, the system730, according to some embodiments, may comprise a conventional airhandling unit 810 for conditioning the circulated indoor air of theenclosed environment 802 and ducts 812 for directing the indoor air flowwithin the system 800. Return air 814 may exit the enclosed environment802, which may be partially exhausted as exhaust air 818, via exhaustducts 820, into the ambient, and may be partially reintroduced into theenclosed environment 802. A portion of the return air 814 may beintroduced into the scrubber 800 prior to flow back into the enclosedenvironment 802. Fresh, outdoor air 830 may be introduced into thesystem 730 via ducts 834.

In accordance with some embodiments, the air ionizer 750 may be providedat any suitable location, such as within the enclosed environment 802 orat an entrance thereto.

The microorganism removal device 760 may be provided at any suitablelocation, such as within the enclosed environment 802, or at an entrancethereto or exit therefrom. Additionally, the removal device 760 may beplaced before entry or after the exit to the scrubber 200.

Moreover the air ionizer 750 or removal device 760 may be placed withinthe scrubber 200, such as the scrubber shown in FIG. 11C.

It is noted in reference to FIGS. 1-11D, that any other suitable meansbesides dampers, such as valves, fans or shutters, may be used tocontrol the volume of air entering and/or exiting the fan-coil unit 128or the scrubber 200.

In some embodiments of the systems shown in FIGS. 1-11D, a single orplurality of sensors (not shown) may be provided to detect levels of oneor more contaminants, substances, gases (such as CO₂ and other gases),fumes, vapors, (such as VOCs) and/or any combination thereof. Thesensors may be placed in any suitable location within the enclosedenvironment 102 or in proximity thereto. Upon detection of a particularconcentration of such contaminants, substances, gases, etc., thesensor(s) may be configured to generate output data that can betransmitted to a control system (not shown) for processing thereof.

The control system may be operative to control any one or more of: theduration of time the scrub cycle and the purge cycle, the volume of airflowing into the scrubber for scrubbing thereof, the volume of purge gasflowing into the scrubber for regeneration of the scrubber, andswitching of the scrubber from the scrub cycle to the purge cycle andvice versa.

In some embodiments, the control system may be designed to control theduration and air volume during the scrub cycle and the purge cycle andswitching of the scrubber from the scrub cycle to the purge cycle andvice versa, according to a preset schedule, or by sensing apredetermined level of the contaminants by the sensors and accordinglyoperating the scrub cycle or purge cycle, or by determining an occupancylevel of the indoor space 120 and, accordingly, operating the scrubcycle or purge cycle, for example. The duration or volume during thescrub cycle or purge cycle and switching therebetween may be controlledby a manual trigger or by externally signaled commands or any othersuitable means.

In some embodiments, the control system may be designed to activate thescrubber in response to actual contaminant levels, occupancy, or presetschedules.

It is noted that the ducts disclosed throughout the application maycomprise conduits, pipes or any suitable means for directing air to flowtherethrough.

Example embodiments of the methods and components of the current subjectmatter have been described herein. As noted elsewhere, these exampleembodiments have been described for illustrative purposes only, and arenot limiting. Other embodiments are possible and are covered by thecurrent subject matter. Such embodiments will be apparent to personsskilled in the relevant art(s) based on the teachings contained herein.Moreover, a feature(s) from one embodiment(s) may be used in combinationor in place of a feature(s) of another embodiment(s). Thus, the breadthand scope of the current subject matter should not be limited by any ofthe above-described exemplary embodiments, but should be defined only inaccordance with the following claims and their equivalents.

What is claimed is:
 1. A system for conditioning air in a building,comprising: a fan-coil unit arranged adjacent to or within an indoorspace within the building and additionally configured to at least one ofheat and cool the air of the indoor space; and a scrubber arrangedadjacent to or within the indoor space, the scrubber configured during ascrub cycle to scrub indoor air from the indoor space, the scrubberincluding: one or more adsorbent materials arranged therein to adsorb atleast one gas from the indoor air during the scrub cycle; and a sourceof purging gas, wherein the scrubber is configured, during a purgecycle, to direct the purging gas over and/or through the one or moreadsorbent materials to purge at least a portion of the at least one gasadsorbed by the one or more adsorbent materials during the scrub cyclefrom the one or more adsorbent materials and thereafter exhaust thepurging gas via an exhaust.
 2. The system of claim 1, wherein thepurging gas includes indoor air from the indoor space.
 3. The system ofclaim 1, wherein flow of indoor air from the indoor space to thescrubber or from the scrubber to the indoor space is ductless.
 4. Thesystem of claim 1, wherein the at least one of heating and cooling theair of the indoor space is performed without introducing outdoor airinto the indoor space.
 5. The system of claim 1, where the at least onegas includes one or more of carbon dioxide, volatile organic compounds,sulfur oxides, radon, nitrous oxides and carbon monoxide.
 6. The systemof claim 1, wherein the one or more adsorbent materials includes one ormore of granular adsorbent particles, solid supported amines, activatedcarbon, clay, carbon fibers, carbon cloth, silica, alumina, zeolite,synthetic zeolite, hydrophobic zeolite, natural zeolite, molecularsieves, titanium oxide, polymers, porous polymers, polymer fibers andmetal organic frameworks.
 7. The system of claim 1, wherein the one ormore adsorbent materials are contained in one or more removablecartridges.
 8. An air treatment system for conditioning air in abuilding, comprising: a fan-coil unit configured to circulate indoor airof an indoor space; heating or cooling means configured to respectivelyheat or cool the indoor air; a scrubber configured, during a scrubcycle, to scrub the indoor air from the indoor space, the scrubberplaced within or adjacent to the indoor space and including one or moreadsorbent materials arranged therein to adsorb at least one gas from theair of the indoor space during the scrub cycle, and a source of purginggas; wherein, during a purge cycle, the scrubber is configured to flowthe purging gas over and/or through the one or more adsorbent materialsto purge the one or more adsorbent materials of at least a portion ofthe at least one gas adsorbed by the one or more adsorbent materials andthereafter exhaust the purging gas via an exhaust.
 9. The system ofclaim 8, wherein the purging gas includes indoor air from the indoorspace.
 10. The system of claim 8, wherein flow of indoor air from theindoor space to the scrubber or from the scrubber to the indoor space isductless.
 11. The system of claim 8, where the at least one gas includesone or more of carbon dioxide, volatile organic compounds, sulfuroxides, radon, nitrous oxides and carbon monoxide.
 12. A method forconditioning air in a building, comprising: circulating indoor air of anindoor space via a fan-coil unit; scrubbing the indoor air during ascrub cycle using a scrubber placed within or adjacent to the indoorspace, the scrubber including one or more adsorbent materials arrangedtherein to adsorb at least one gas from the air of the indoor spaceduring the scrub cycle; flowing a purging gas over and/or through theone or more adsorbent materials so as to purge the adsorbent materialsof at least a portion of the at least one gas adsorbed by the one ormore adsorbent materials; and thereafter exhausting the purging gas flowvia an exhaust.
 13. The method of claim 12, wherein the purging gasincludes indoor air from the indoor space.
 14. The method of claim 12,wherein the fan-coil unit is supplied refrigerant or heating fluid froma variable refrigerant flow (VRF) system.
 15. The method of claim 12,wherein the fan-coil unit is supplied chilled or heated water from acentral chiller or boiler.
 16. The method of claim 12, wherein thescrubber further comprises at least one of a damper and a fan, themethod further comprising switching the scrubber from the scrub cycle tothe purge cycle using the at least one of the fan and the damper. 17.The method of claim 16, further comprising performing the switchingaccording to at least one of: a preset schedule, a predetermined levelof the at least one gas, the indoor space occupancy level, a manualtrigger, a signaled command and an externally signaled command.